SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '642e5beba24550010afe29bbc03b504046d0348f4f0def400f6f178ba64fc9e0' 
  AND token = '2irzEtfj1yLJDzIF0t5LGfENPZCUNek6Kz8tmGaOd5A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}